During the Olympic Opening Ceremony on July 27, around 10,000 performers, 70 sheep, 12 horses, ten chickens, three cows, and two goats will entertain a crowd of 80,000. For the past two years, costume designer Suttirat Larlarb has been dreaming up the elaborate costumes for the spectacle. Larlarb recently spoke with TIME about the scale of the show, how designing for the Olympics is different than designing for movies, and what it’s like to work with film and Olympic Opening Ceremony director Danny Boyle.

You’ve worked on blockbuster motion pictures like Slumdog Millionaire and The American. How does the scale of the Opening Ceremony compare with the scale of a film?

I’d say it probably comes closest to Slumdog just in the sense of the massive numbers of people, and a cast of thousands of real people. But the Opening Ceremony is more overwhelming and relentless.

How so?

Every day one has to have a moment to take stock of what you’ve achieved, because it never really feels like you’ve made a dent in anything, even though we’re very far along in the process. As a team we’ve been on it for close to two years. That’s probably the biggest difference: the amount of time spent preparing for essentially one shot at something. On a film you’ve got maybe six to eight months of prep time, but you then have 12 weeks to shoot something, so you revisit, and you have time to constantly tweak it. But this is two years of prep for one evening. It’s kind of unfathomable.

Oh, it’s seven days a week. The shortest days are probably 16 hours a day for me, because so much of the cast are volunteers – real people from London, not professionals. We structure the rehearsals and fittings and anything to do with them off working hours. So I spend my day prepping and then we have these mass costume sittings in the evenings and on weekends. There are pretty much no days off.

You worked with director Danny Boyle on Slumdog Millionaire. Is he approaching this like he would a movie?

I’ve always thought of him as someone who has a very theatrical vision. Everything is about character and narrative, and it’s not just about stunning visual flash for a big screen. With the Olympics you have a live audience of 80,000 people in the stadium, but then you have this projected television audience of billions. We don’t want to rob the stadium audience of anything because we’re only thinking about the television audience. What happened in Beijing was a completely massive, spectacular, overwhelmingly beautiful television experience. And yet some people will say that when they were in the stadium they didn’t feel connected to it at all because it was devised for the television.

What were your other goals?

We wanted to make sure that we left people with something more than just a visual spectacular to go home and talk about. We took very seriously the points of Olympic protocol but we wanted to make sure they were not just a laundry list of “tick, the torch has come in” and “tick, the head of state is speaking now.” We want to make sure all those moments are as juicy as every other moment. As for the cultural part of the show, his goal was to make sure that we kept it human and therefore emotional. There aren’t just empty pictures of history lessons. We want people to feel something. It’s quite a ride, and every week we accomplish more and see things coming together. I don’t think I’ve ever had so many spine-tingling moments just looking at a prototype of something.

Danny has a reputation for working around-the-clock. Has that been the case?

He expects everybody to work as hard as he does, and he works really hard. He’s not a dilettante. He’s not somebody who swans in and says, “Yeah, I don’t know, maybe not that.” He does an insane amount of work. I’m not sure that he sleeps. He’s incredibly focused and driven and everything can always be improved. He’s inspired by every little action of the day, like riding the Tube into work.

So at this stage in the game, is it now just a matter of perfecting it?

Yes, there’s that – there’s very much finessing to be done. But it’s not done and dusted at all. It’s because of the scale of it. There’s only so many hours in the day, and there’s only so much you can attend to in one day, which means that other stuff is still hanging in the balance, so it’s very much going to be up until the day that we’re working as intensely as we are now. It’s just an immense undertaking. I don’t think anybody could do this, take this on board, have a nice leisurely lunch and come back to the studio and say, “Oh, just make it pink.” There’s millions of decisions to be made, and things being put in front of you that are based on suggestions and decisions you’ve made prior, and suddenly things become unavailable so you have to rethink them. It’s a constantly evolving process and everything has a domino effect, based on when you’ve made a decision, and what’s available in the world, and what’s available with this amount of money, and this amount of workforce.

Will you guys be watching in the audience, or will you be on the ground troubleshooting?

I haven’t quite made up my mind. But I can’t just sit there and watch it calmly with the audience. I will be in the stadium somewhere. I might be in one of the technical booths, or I might be down on the ground.